Bis trimethylsilyl

Trimethylsilyl triflate itself can not promote allylation reactions of aldehydes with allyltri-methylsilane. By using the more highly reactive system Me3SiB(OTf)4, the reactions proceed smoothly.326 A very small amount (0.2-1 mol.%) of Me3SiB(OTf)4 is enough for the reactions (Scheme 75). Allylation of acetals can be promoted by trimethylsilyl bis(trifluoromethanesulfo-nyl)imide (Me3SiNTf2),327 which is also a reactive catalyst for Diels Alder reactions.328... 

Kaur G, Trehan A, Trehan S (1998) Highly efficient deprotection of acetals and ketals under neutral and anhydrous conditions using (trimethylsilyl)bis(fluorosulfuryl)imide. J Org Chem... 

Protodesilylation of allyl- or aryl-substituted trialkylsilanes with an acid partner is a cleaner method, producing propene or an aromatic hydrocarbon as a volatile inert byproduct. Although some methods of isolation have been reported, they can usually be prepared in situ in aprotic media and employed without further purification. Methods of preparation of representative organosilicon Lewis acids, la, trimethylsilyl bis(trifluoro-methanesulfone)imide (7) [9], trimethylsilyl perchlorate (6a) [10], iodotrimethylsilane, and trimethylsilyl tetrakis(trifluoromethanesulfonyl)borate [11] are described below. In principle, these analogs are also accessible in a similar manner (Table 1) [2d]. 

Cyanohydrins and ethers. The react catalyzed, so that it can be used to different Dibutyltin dichloride can be used as a cal Trimethylsilyl bis(fluorosulfonyl)imide is derivatization at -78° (11 examples. 84-989 Ritter reaction. A combination of V hydroxy group to a formamido function. 

Mathieu B, Ghosez L (1997) N-trimethylsilyl-bis(trifluoromethanesulfonyl)imide a better carbonyl activator than trimethylsilyl triflate. Tetrahedron Lett 38 5497-5500... 

From bis(trimethylsilyl)-, bis(triethylgermanium)- or bis(tributyltin)carbodiimides with benzenesulfonyl isocyanate, cyclic 1 1 and 1 2 adducts are produced . ... 

Incubations were set up as specified in Fig. 3, resulting in the consumption of more than 90 % of the substrates according to n. m. r. analysis of suitable model compounds the methionine produced was isolated by ion exchange technique and subsequently converted into its bis-trimethylsilyl (bis-TMS) derivatives upon reaction with N-(trimethylsilyl)diethylamine. Control experiments, in which the substrates, or homocysteine, were omitted from the incubations, gave no trace of methionine. A non-catalyzed methionine formation, detectable in the absence of the enzyme preparation, proceeded with a rate too low to seriously compete with the enzyme-catalyzed reaction. 

The Lewis acid-promoted reaction of acetals with trimethylsilyl (TMS) enolates is valuable for the synthesis of p-alkoxy carbonyl compounds, that is, O-alkylated aldols [44]. This aldol-type reaction is effectively catalyzed by (la) [7d, 43], trimethylsilyl iodide (MesSil) [45] and trimethylsilyl bis(fluorosulfonyl)amide (Me3SiN(S02P)2) [46]. Recently, bis (trifluoromethanesulfonyl) amine (HNTf2) has been found to catalyze the aldol-type reaction. A comparison of HNTf2 with Me3SiNTf2 (lb) in catalytic activity suggests that an initial protodesilylation of TMS enolates with HNTf2 forms (lb) as the actual catalyst [47] (Scheme 9.8). 

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